[see structure]. An efficient, concise approach to the macrolide core of the cryptophycins, potent antimitotic agents, has been achieved. The reaction sequence features a novel macrolactonization utilizing a reactive acyl-beta-lactam intermediate that incorporates the beta-amino acid moiety within the 16-membered macrolide core. This highly modular approach, which allows for multiple alterations throughout
[请参阅结构]。对于隐藻霉素的大环
内酯类核心化合物(一种有效的抗有丝分裂剂),已经实现了一种有效,简洁的方法。该反应序列具有利用反应性酰基-β-内酰胺中间体的新型大环内酯化作用,该中间体在16元大环内酯核内掺入了β-
氨基酸部分。这种高度模块化的方法可以在整个结构中进行多种更改,已成功地应用于隐藻素24的总合成中。